At present, a fairly large number of methods and apparatuses are known that allow enhancement of production processes for high-viscosity oils. In most cases, these techniques employ physicochemical methods of influence on a stratum (well bottom zone) and on transport systems that transport oil from the stratum to the surface. In particular, it is proposed to add different reagents into a well and to influence strata by elastic vibrations of different frequency, shock waves, magnetic and electric fields or combinations thereof. In some cases, the use of devices that include sources of elastic vibrations and systems of induction heating are provided.
A method for intensification of oil production by the excitation of elastic vibrations in a stratum and the well bottom zone is known (U.S. Pat. No. 5,950,726 A, published on Jan. 31, 1991). Elastic vibrations are excited by use of a hydraulic vibration generator, by a cyclic change of pressure in liquid being supplied. The excitation of elastic vibrations leads to a decrease in the viscosity of oil, a rise in the permeability of a reservoir and an increase in the output of a well.
The disadvantage of this method is that it does not provide for the effects on oil during its transport by oil-well tubing, thus decreasing the efficiency of the method.
A prototype of the first object of the proposed invention is a method for development of oil pool (RU 2184842 C2, published on Jul. 10, 2002), where stimulation of producing formation with a heat source and source of elastic vibrations is proposed. A heat source is placed inside an injection well. Treatment with the heat source is carried out with periodic variation of its power. A source of elastic vibrations is installed on the surface of the wellhead of the oil producing well. Heat source and source of clastic vibrations operate at the same frequency and periodically constant difference of phases. The effect obtained is the most complete withdrawal of oil due to varying of oil viscosity and phase permeability of reservoir for oil and water.
The disadvantage of the method is its insufficient efficiency because it does not provide for the effect on oil during its transport by oil well tubing.
A device for the production of high-viscosity oils is known (RU 2198284 C2, published on Feb. 10, 2003) that involves the use of an induction well electric heater. In this device, oil-well tubing (OWT) fitted with metal rings with slits, is a casing and at the same time a magnetic core. Wires of an induction coil wound on the external surface of the casing are laid through slits. The use of the device allows heating of the oil being extracted due to the conversion of electrical energy into thermal energy.
The disadvantage of this device is that it does not provide for the additional effect on the stratum and oil in the well bottom zone, decreasing the efficiency of the device.
A prototype of the second object of the proposed invention is a thermo-acoustic well apparatus (SU 1086131 A, published on Apr. 15, 1984) that allows conducting the simultaneous heating and irradiation of oil stratum in the well bottom zone with ultrasound using a magnetostrictive radiator, which increases the inflow of oil into a well.
The disadvantage of the device is that the treatment is carried out only in the oil stratum without the heating of OWT, which decreases the efficiency of the device during oil production.
Acoustic Well Recovery Method and Device Patent Application U.S. Ser. No. 10/615,230, proposes a method for acoustic stimulation and the devices for its implementation, characterized because it comprises an electric generator and a vibratory system placed inside the well. The method proposed in patent application, U.S. Ser. No. 10/615,230, promotes the formation of shear vibrations in the extraction zone. The disadvantage of said Application in relation to the production of high viscosity fluids lies in the fact that it does not consider neither the heat generated in the extraction zone or the stimulation of recovered fluids during transport to the surface through the oil well tubing.